The cluster of galaxies MACS J1149.5+2223 is so massive that it has gravitationally bent (or lensed) the light from multiple things behind it, including one of the most distant galaxies in the universe and a supernova.

NGC 34 (also known as NGC 17) is a chaotic-looking galaxy that formed from two smaller galaxies merging together, and it is a place where astronomers have easily found lots of stars forming in a starburst but where they have had difficulty concluding whether the galaxy also contains a supermassive black hole.

The Monogem Ring, which is one of the largest sources of X-rays in the Earth's sky, was created by a supernova explosion about 86000 years ago, and the core of the star that exploded has been identified as the pulsar PSR B0656+14 at the center of the ring.

Even though Alpha Mensae is in one of the faintest and dumbest constellations in the sky, it's an intriguing star system because it is very close to the Earth, because one of the stars is very Sun-like, and because it may contain an exoplanet or a disk of dust in orbit around that Sun-like star.

The Type Ia supernova SN 2005cf was observed at multiple wavelengths for three months after its appearance, allowing astronomers to create templates of its spectrum that could be used to measure distances to other Type Ia supernovae.

Kappa Cassiopeiae is a large blue variaable star that is most potentially interesting because of the bow shock between its stellar winds and the interstellar medium.

47 Ursa Majoris is a nearby Sun-like star that astronomers have intensely studied in an effort to find an Earth-like exoplanet, and while three exoplanets have been found orbiting the star, none of them are remotely similar to the Earth.

While the planetary nebula NGC 1501 is a popular amateur astronomy target, the newly formed, hot, pulsating white dwarf at its center is much more interesting to professional astronomers.

As the second closest spiral galaxy to the Milky Way, Messier 33 has been a very popular observing target for both amateur and professional astronomers, and even I have made images of the galaxy.

The white dwarf GD 394 seems to have an abnormal amount of heavy elements in its outer atmosphere and also varies in brightness with a period of 1.146 days, and no one understands why.

The Norma Cluster lies near the center of a giant supercluster of galaxies that is pulling in everything else in the local universe, including our galaxy.

The classical nova RR Pictoris was one of the brightest and closest to ever appear in the sky.

The spiral galaxy Markarian 766 contains an active galactic nucleus with a supermassive black hole, which means that everyone needs to apply their favorite technique to measure the black hole's mass.

The Kepler-138 star system contains at least four exoplanets, one of which may be a "water world" covered in a very deep ocean.

The protostellar object PDS 70 has a very complicated protoplanetary system that includes a disk of gas and dust and two protoexoplanets.

The Red Rectangle (yes, the Red Rectangle) is a uniquely weird protoplanetary nebula formed by a uniquely weird binary star system.

While some astronomers are interested the globular cluster NGC 6712 because it appears to have been severely tidally disrupted by orbiting too close to the center of the Milky Way, other astronomers are interested in the cluster because it contains a couple of weird yet similar binary star systems.

Located at the edge of the Local Group, the Sagittarius Dwarf Irregular Galaxy has some of the stars with the fewest elements other than hydrogen or helium in the known universe.

Observations with a telescope as large as the Untied States were needed to prove that J16021+3326 is a blazar, a type of galaxy containing a supermassive black hole.

PSR B1509-58 is a relatively young pulsar that sits within a supernova remnant that looks like a giant hand.